Antibacterial fibers may be used in manufacture of fabrics, condoms, filters, diapers, bed linens, and other articles in which it is desirable to kill or retard growth of bacteria, fungi or viruses. A variety of approaches have been used to produce such fibers. For example, PCT publication WO 98/06508 describes an antibacterial textile in which fibers are plated with a metal or metal oxide. U.S. Pat. No. 7,169,402, which is incorporated herein by reference, describes polymers such as polyamide, polyester, and polypropylene which contain microscopic particles of copper oxide and exhibit antibacterial properties.
Viscose rayon is a manufactured regenerated cellulosic fiber widely used in manufacture of textiles (e.g., apparel), feminine hygiene products, and medical surgical products. The process of manufacturing viscose rayon usually includes the following steps (or equivalents): (1) Steeping, (2) Shredding, (3) Aging, (4) Xanthation, (5) Dissolving, (6) Ripening, and (7) Spinning. The various steps involved in the process of manufacturing viscose are known in the textile arts (see, e.g., Encyclopedia of Chemical Technology Third Edition, 1982, Vol. 19, pages 855-880, John Wiley & Sons, which is incorporated herein by reference) and are described below.
Rayon textiles asserted to have antibacterial properties have been described. For example, Daiwabo Rayon Ltd (Japan) markets rayon containing light-responsive ceramics purported to have antibacterial properties. U.S. Pat. No. 6,344,077 describes rayon containing chitosan, alginic acid or derivatives of these compounds purported to have antibacterial properties, and to be water-soluble. However, a need remains for rayon fibers that are stable, economical, and have effective antimicrobial, antifungal and antiviral properties.